Least Count (L.C)=NP=500.5mm=0.01mm
Length of wire =6.8cm
Diameter of wire =1.5mm+7× L.C
=1.5mm+7×.01=1.57mm
Curved surface area =πDl
=3.14×6.8×1.57×10−1cm2
=3.352cm2=3.4cm2
JEE Main 2022 — Physics Mechanics
A screw gauge of pitch 0.5mm is used to measure the diameter of uniform wire of length 6.8cm, the main scale reading is 1.5mm and circular scale reading is 7. The calculated curved surface area of wire to appropriate significant figures is
[Screw gauge has 50 divisions on the circular scale]
Held on 26 Jul 2022 · Verified 6 Jul 2026.
6.8cm2
3.4cm2
3.9cm2
2.4cm2
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